Moduleoptics-extra-0.4.2.1Haskell2010

Optics.State.Operators

Defines infix operators for the operations in Optics.State. These operators are not exposed by the main Optics module, but must be imported explicitly.

Contents

State modifying optics
State modifying optics with passthrough
Returning new value
Returning old value
Passthrough

Synopsis

value .=
value ?=
value %=
value %%=
value <.=
value <?=
value <%=
value <<.=
value <<?=
value <<%=
class PermeableOptic

Packageoptics-extra-0.4.2.1
Exports11
LanguageHaskell2010
LicenceBSD-3-Clause
SourceOperators.hs

State modifying optics

value(.=) :: (Is k A_Setter, MonadState s m) => Optic k is s s a b -> b -> m ()

Source#

Replace the target(s) of an Optic in our monadic state with a new value, irrespective of the old.

This is an infix version of assign.

value(?=)

:: (Is k A_Setter, MonadState s m)
=> Optic k is s s (Maybe a) (Maybe b)
-> b
-> m ()

Source#

Replace the target(s) of an Optic in our monadic state with Just a new value, irrespective of the old.

value(%=)

:: (Is k A_Setter, MonadState s m)
=> Optic k is s s a b
-> a -> b
-> m ()

Source#

Map over the target(s) of an Optic in our monadic state.

This is an infix version of modifying.

State modifying optics with passthrough

value(%%=)

:: (PermeableOptic k r, MonadState s m)
=> Optic k is s s a b
-> a -> (r, b)
-> m (ViewResult k r)

Source#

Modify the target of an PermeableOptic in the current state returning some extra information of type depending on the optic (r, Maybe r or monoidal summary).

Returning new value

value(<.=)

:: (PermeableOptic k b, MonadState s m)
=> Optic k is s s a b
-> b
-> m (ViewResult k b)

Source#

Set with pass-through.

This is useful for chaining assignment without round-tripping through your Monad stack.

value(<?=)

:: (PermeableOptic k (Maybe b), MonadState s m)
=> Optic k is s s (Maybe a) (Maybe b)
-> b
-> m (ViewResult k (Maybe b))

Source#

Set Just a value with pass-through.

This is useful for chaining assignment without round-tripping through your Monad stack.

value(<%=)

:: (PermeableOptic k b, MonadState s m)
=> Optic k is s s a b
-> a -> b
-> m (ViewResult k b)

Source#

Modify the target of a PermeableOptic into your Monad's state by a user supplied function and return the result.

Returning old value

value(<<.=)

:: (PermeableOptic k a, MonadState s m)
=> Optic k is s s a b
-> b
-> m (ViewResult k a)

Source#

Replace the target of a PermeableOptic into your Monad's state with a user supplied value and return the old value that was replaced.

value(<<?=)

:: (PermeableOptic k (Maybe a), MonadState s m)
=> Optic k is s s (Maybe a) (Maybe b)
-> b
-> m (ViewResult k (Maybe a))

Source#

Replace the target of a PermeableOptic into your Monad's state with Just a user supplied value and return the old value that was replaced.

value(<<%=)

:: (PermeableOptic k a, MonadState s m)
=> Optic k is s s a b
-> a -> b
-> m (ViewResult k a)

Source#

Modify the target of a PermeableOptic into your Monad's state by a user supplied function and return the old value that was replaced.

Passthrough

classclass (Is k A_Traversal, ViewableOptic k r) => PermeableOptic (k :: OpticKind) r where

Methods

passthrough :: Optic k is s t a b -> (a -> (r, b)) -> s -> (ViewResult k r, t)
Modify the target of an Optic returning extra information of type r.

Instances5PermeableOptic

Monoid r => PermeableOptic A_Traversal rDefined in optics-extra-0.4.2.1 · Optics.Passthrough
PermeableOptic A_Lens rDefined in optics-extra-0.4.2.1 · Optics.Passthrough
PermeableOptic A_Prism rDefined in optics-extra-0.4.2.1 · Optics.Passthrough
PermeableOptic An_AffineTraversal rDefined in optics-extra-0.4.2.1 · Optics.Passthrough
PermeableOptic An_Iso rDefined in optics-extra-0.4.2.1 · Optics.Passthrough